1. Field of the Invention
The present invention relates generally to a method and apparatus for receiving a broadcast service in a wireless mobile communication system. In particular, the present invention relates to a method and apparatus for providing and receiving a broadcast service using common radio resources.
2. Description of the Related Art
The future communication environment is expected to undergo a sudden change regardless of wire/wireless zone, district, or country. Particularly, in an International Mobile Telecommunication-2000 (IMT-2000) environment which is the typical future communication environment, not only voice and image but also various information needed by a user are collectively provided in real time. The development of mobile communication systems enables a user of an access terminal (AT, also known as a mobile station) such as a cellular phone or a Personal Communication System (PCS) phone not only to transmit text information but also to view a broadcast service including high-speed image, voice and sound, beyond the basic voice communication.
In a broadcast service in the conventional mobile communication system, upon detecting the fact that a broadcast service is supported within a cell, an access terminal acquires information (for example, a connection identifier (CID) and an encryption key) used for receiving a physical channel and information (for example, a program list, a multicast Internet Protocol (IP) address, and a port number) used for receiving a broadcast, from an access point (AP, also known as a base station), before receiving the corresponding broadcast. To this end, the access terminal should acquire the same broadcast-related information no matter the cell in which the access terminal is located.
FIG. 1 is a diagram illustrating a system configuration in which all cells provide the same broadcast service. As illustrated, because all of the cells covered by their own access points provide the same broadcast service, an access terminal 10 can receive the broadcast service in all of the cells using the same program information provided from any one of the access points and its associated physical channel information.
However, assuming that different local broadcasts are provided in two different cells and broadcast reception information acquirable from one zone and its associated physical channel information are different from broadcast reception information acquirable from another zone and its associated physical channel information, when an access terminal in receiving a broadcast crosses over the boundary between the two different zones, the access terminal cannot recognize a broadcast service of the new zone.
That is, in the conventional mobile communication system, when a new zone provides a broadcast service of a different content using physical channel information that is different from that of the original zone, an access terminal receiving a particular broadcast channel continuously attempts to receive the broadcast service using its old zone's physical channel information without recognizing the fact that the broadcast service changes when it crosses over the boundary between the zones. In this case, therefore, the access terminal enters a broadcast failure state without recognizing the fact that it is in a new zone and still trying to receive the broadcast associated with the previous zone.